This invention relates to the dispensing of fasteners, particularly fasteners which are included in an assemblage from which individual fasteners are dispensed as desired.
One common form of fastener is of the type disclosed in U.S. Pat. Nos. 3,103,666; 3,444,597; 3,733,657; and 4,039,078. The individual fasteners in assemblages of the kind disclosed in the foregoing patents include opposite end members that are interconnected by a transverse segment commonly designated a "filament". Generally one of the end members is a "cross bar" in the form of a short cylindrical element disposed at a right angle to the filament and proportioned to be dispensed through the bore of a slotted hollow needle. In the course of dispensing a fastener, its cross bar is moved through the bore with the filament extending through the slot of the needle. The member opposite the cross bar is in accordance with the intended function of the fastener. One common form of opposite end member is a transverse enlargement commonly known as a "head" or "paddle". It is used, for example in supporting an information bearing tag which is attached to an item of merchandise such as a garment by the dispensing device.
The dispensers for such fasteners are generally of the kind disclosed in U.S. Pat. Nos. 3,103,666; 3,470,834; Re 29,310; 3,893,612; 3,875,648; and 4,111,347.
The expulsion mechanism of the foregoing dispensing devices generally includes an elongated slide as shown in U.S. Pat. Nos. 3,103,666 and Re. 29,310 in order to achieve simultaneous operation of the feed mechanism and the plunger by which individual fasteners are expelled from the device.
An alternative construction is of the type shown in U.S. Pat. Nos. 3,650,451; 3,650,452; and 3,924,788. This construction requires that the housing for the dispensing apparatus allow for the pivotting of a lever which acts upon the feed and dispensing mechanisms. The result is an increase in bulk over and above what would otherwise be required.
In addition it is desirable to provide a release mechanism to permit clearing of the device or release of any occasional jams that may occur. One type of release mechanism operates only when the trigger is depressed. This is cumbersome and inoperable in many situations. Another type of release mechanism disables both the drive and feed mechanisms of the gun. This adds complexity to the mechanism. It is additionally undesirable since operation of the drive mechanism is often useful in clearing a jam. Thus if the drive is interrupted during clearance, the clearance procedure becomes more difficult to accomplish. Still another type of release mechanism disables the feed mechanism at a portion remote from the pawl. As a result the clearance procedure must be undertaken with care.
Another characteristic of the ordinary dispensing device is that the feed takes place using a pawl which engages, for example, sprocket teeth of a feed wheel. In the ordinary construction there is a significant amount of wear that takes place in the pawl over the course of time. The result is that the ordinary attacher gun has a limited life. It is not possible for the customer to repair the worn pawl and the dispensing device must therefore be returned to a service center for repair.
Accordingly, it is an object of the invention to facilitate the dispensing of fasteners. A related object is to facilitate the dispensing of individual fasteners from an assemblage in which each individual fastener includes end members that are joined by a cross member commonly referred to as a filament.
A further object of the invention is to simplify the control lever that is used in actuating both the feed and expulsion mechanisms simultaneously. A related object is to achieve compactness in the design of devices for dispensing fasteners by reducing slide length and eliminating the customary pivoted lever of the prior art.
Still another object of the invention is to facilitate the release of assemblages that have been inserted into dispensing devices, as well as the clearance of jams. A related object is to achieve release and clearance without disabling the drive function of the device.
Another object of the invention is to prolong the life of the device by reducing the incidence of wear that commonly takes place between a feed pawl and a drive sprocket. A related object is to achieve increased wear with a simplified pawl.